Relay



H. A. MILOCHE RELAY Filed Nov. 21, 1947 /Nl/EA/rop h. A. M/LOCHE Br W Arron/wir April l, 1952 Patented Apr. 1, 1952 RELAY Herman A. Miloche, Teaneck, N. J., assigner to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application November 21, 1947, Serial No. 787,348

(Cl. 20G-104) Claims.

This invention relates to electromagnetic relays and more particularly to relays used in telephone switching circuits.

An object of the invention is to attain a high degree of efficiency, compactness, and economy of manufacture in an electromagnetic relay.

Another object is to simplify and reduce the mass of the moving parts of a relay.

Another object is to increase the efficiency of the magnetic circuit of a relay.

A further object is to provide ready interchangeability of parts in order that a relay may be readily adapted to meet a particular set of requirements.

'Ihe applicant has accomplished these objects by mounting the contacts springs, core, coil, armature, and cards so that their axes are all parallel. The contact springs are mounted circumferentially in a base member so as to extend parallel to and surrounding a core and coil structure, the armature is pivotally mounted about its center so as to be rotatable about the axis of the core, and the circular xed and movable cards or spring-controlling members are mounted in planes parallel with the armature and are peripherally notched to engage the contact springs. By this novel design, the armature and movable card are rotatable through a small angle in a plane perpendicular to the axes of the contact springs and apply an actuating force on the movable contact springs tangential of the circular card, and, similarly, the resisting force on the fixed contact springs is exerted tangentially of the circular fixed card.

Since the diameter of the movable card is greater than the diameter of the path of the armature, a small rotary movement of the armature results in a magnified movement of the contact springs and thus but a small armatureto-core air gap is required to produce the requisite movement of the contact springs, and a highly eicient magnetic circuit is thereby obtained. This improved relay design has further permitted the employment of moving parts having little mass, thereby enhancing the speed of operation and release of the relay.

In an effort to reduce the number of components in order to simplify the relay and reduce the cost of manufacture and maintenance, the functions normally accomplished by armature backstops and armature support or biasing lsprings have been relegated to the cards and contact springs. A third circular card maintained in nxed relationship to the core, is properly apertured to pretension certain of the contact springs in a direction opposite to that in which they are to move upon operation of the relay, and these pretensioned springs therefore normally exert a force which serves to restore the armature to its unoperated position upon 'deenergization of the coil. The backstop function is performed by certain of the contact springs which are held by the xed card and.

against which the edges of certain of the notches in the movable card rest when the relay is in an unoperated position.

As will be subsequently shown, the various elements of the structure are removably interattached in order that the coil and card may be readily changed to render the relay adaptable to meet a variety of requirements.

The invention may be more completely understood by reference to the accompanying drawings in which:

Fig. 1 is a perspective view of a relay constructed in accordance with the invention;

Fig. 2 is a section through the axis of the relay shown in Fig. 1 with the cover in place; and

Fig. 3 is a section taken through 3 3 of Fig. 2, showing the interrelationship of the operating members of the relay.

Referring now particularly to Figs. 1 and 2, a substantially E-shaped core I of magnetic material, is aiflxed to an insulating base member 2 by means of a screw 3. The core I comprises two outer legs 4 and a center leg 5 all extending parallel one to the other. An energizing coil 6 havingspoolheads I and 8 thereon is arranged to be removably mounted on the center core leg 5. A low-mass armature 9 is pivotally mounted on the center core leg 5 by means of a screw ID having a shank II about which the armature 9 is rotatable. As may be seen in Fig. 3, the armature 9 is thereby pivotal about an axis through its center and has surfaces I2 which are matable with the outer core legs 4 upon energization of the coil 6.

A plurality of wire contact springs I3 are molded or otherwise secured in the base member 2, extend rearwardly therefrom to provide wiring terminals I4, and extend forwardly therefrom in approximate parallelism with the core legs 4 and 5. The contact springs I3 are equally spaced and circularly arranged in the base member and extend upwardly so as to describe a cylinder around the core and coil structure. Contacting elements I5 at the operating ends of each contact spring I3 are in the form of the armature about an axis parallel with that of the core legs 4 and 5. A xed card I mounted between the armature S and the upper coil spool- 5 head 8 has apertures suitably located therein through which the outer core legs 4. and the screw It may pass. The fixed card I8 is therefore iixedly positioned by the outer core legs II, the upper coil spoolhead 8, and the shank II of the screw Ill. A second xed card I9 is removably supported on outer core legs 4 at a position approximately midway between the xed card I8 and the base member 2, and is prevented from rotating by having notches 3i therein engageable with said outer core legs 4. The two xed cards I8 and I9 are each of circular conguration and are suitably apertured around their peripheries to accept the contact springs I3.

The location and size of the apertures in the three cards It, i8, and l determines whether the several contact springs i3 will serve to make break, or transfer? electrical circuits or a combination of these functions, which shall hereinafter be referred to as the coding of the relay. In the embodiment depicted in the accompanying drawings, each of these types of circuit control has been shown. For example, upon the operation of the relay, contacts 2li, 2I and 22 will transferf contacts 23 and 24 will make and contacts 25 and 2t will break electrical circuits. In order that the contact springs shall operate in the desired manner, certain of the springs must be pretensioned in a direction opposite to that in which they are subsequently to move, and this is accomplished by means of'the lower xed card IQ. Certain of the apertures in this card are located .in exact vertical alignment with the point at which their associated contact springs pass through the base member 2, whereas certain other of the apertures are slightly offset along the circumference of the card so that their associated contact springs are tensioned against the direction of rotation of the movable card It. The upper ixed card IS is suitably notched so that the non-pretensioned springs are firmly held in aiiixed position, while those springs which are pretensioned are free to move the required distance in the direction of rotaticn of the movable card but are restrained from moving in the opposite direction. The movable card it is suitably notched so that upon its rotation certain of the springs are moved and certain others are unaffected by its movement.

The operation of the springs for each of the circuit-controlling functions will now be described with reference to Figs. 1 and 3.

Contact springs 2i), 2l and 22 cooperate to transfer an electrical circuit from contacts 2i and 22 to contacts 2l and 29 upon operation of the relay. Spring 28 is pretensioned, restrained in the unoperated position of the relay by the xed card I8, and is free to move slightly in the direction of rotation upon operation. Spring 2I is pretensioned, restrained in the unoperated position of the relay by the fixed card I 3, and is in contact. Upon operation, this contact is broken and spring 2| is moved into contact with spring 20, the latter of which is free to give slightly under the impact.

Contact springs 23 and 24 cooperate to make an electrical connection with each other upon operation of the relay. Both springs are pretensioned against the xed card I8 but are free to move in the direction of rotation of the movable card. Upon operation of the relay, spring 2i is moved by the movable card I6 into contact with spring 23.

Contact springs 25 and 2S cooperate to break an electrical connection upon operation of the relay. Spring 26 is pretensioned against the fixed card I8 and is free to move in the direction of rotation of the movable card. Spring 25 is not pretensioned and is rmly held by the fixed card i8. Upon operation of the relay spring 26 is moved out of contact with spring 25 by movable card I6.

As may now be more clearly understood, the springs which are pretensioned also serve as armature biasing or restoring springs, exerting a pressure against the movable card and serving to return the armature to its unoperated position upon deenergization of the coil. Further since in the unoperated position of the relay all springs rest against the edges of their respective notches in the iixed card I8, the contact of the notches in the movable card It against certain of the contact springs I3 upon deenergization of the relay prevents the movable card from rotating beyond a certain point, and therefore serves as an armature backstop.

As has been seen, the coding of the relay is determined by the notching of the three cards I6, i8 and i9, each of which is removable upon the removal of the screws l0 and I'I, and therefore the adapting of the relay to meet a particular set of requirements may be expeditiously accomplished by the installation of a suitable set of cards.

Since the armature and movable card rotate about a common axis and since the diameter of the card is appreciably greater than that of the path of the armature, but a relatively small movement of the armature is required to accomplish the requisite movement of the springs, thereby permitting a small armature-to-core air gap and thus providing a highly eicient magnetic circuit.

The circular cylindrical shape of the relay permits the use of an inexpensive tubular cover (Figs. 2 and 3) which may be supported by projections 28 (Fig. l) on base member 2 engaging a slightly fluted portion 2S (Fig. 2) near the ibase of the cover 2.

Apertures 3i! in base member 2 are provided for mounting the relay in position.

As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawings, is to be interpreted as illustrative and notY in a limiting sense.

What is claimed is: I

1. In a relay, a core, an energizing coil on said core, an armature rotatably mounted on said core andattractablel thereto upon, theenergization of said coil, a card of insulating material connected to and rotatable by said armature, a base member, a, plurality of contact springs circularly mounted in said base member and engaging apertures in the perimeter of said card, a second card of insulating material having apertures in the perimeter thereof to hold certain of said springs stationary in relation to certain other of said springs, and a third card of insulating material having apertures in the perimeter thereof to pretension certain of said springs.

2. In a relay, a core, an energizing coil on said core, an armature rotatably mounted on said core and attractable thereto upon the energization of said coil, a first circular card of insulating material connected to and rotatable by said armature, a, second circular card of insulating material supported by said core, a base member, a plurality of contact springs mounted in said base member and engaging apertures in the perimeter of each of said cards whereby upon the operation of said armature certain of said springs are moved in relation to certain other of said springs, and a third card of insulating material having apertures in the perimeter thereof to pretension certain of said springs.

3. In a relay, an E-shaped core, an energizing coil on the center leg of said core, an armature rotatably mounted on the center leg of said core and attractable to the outer legs of said core upon the energization of said coil, a first circular card of insulating material connected to and rotatable by said armature, a second circular card of insulating material supported by the outer legs of said core and adjacent said first card, a base member, a plurality of contact springs circularly mounted in said base member, extending substantially parallel to said core, and engaging apertures in each of said cards whereby upon the operation of said armature certain of said springs are moved in relation to certain other of said springs, and a third circular card of insulating material supported by the outer legs of said core and having apertures therein to accept said springs whereby certain of said springs may be pretensioned.

4. In a, relay, a pair of contact springs, the contact end of one of said springs being movable, means for moving the movable one of said springs into and out of engagement with the other one of said springs as desired, said means comprising a core, an energizing coil on said core, an armature mounted on said core and attractable thereto upon energization of said coil, a movable card of insulating material connected to said armature and a projection on said card having a rst edge engaging said movable spring, and means for xing the unoperated position of said card comprising means for holding the other one of said springs stationary relative to said card and a second edge on said projection opposing said rst edge and normally engaging said other one of said springs to position said movable card and to thereby serve as a backstop for said armature While said coil is deenergized.

5. In a relay, a pair of contact springs, the contact end of one of said springs being movable, means for moving the movable one of said springs into and out of engagement with the other one of said springs as desired, said means comprising a core, an energizing coil on said core, an armature rotatably mounted on said core and attractable thereto upon energization of said coil, a movable circular card of insulating' material connected to and rotatable by said armature and a projection on said card having a rst edge engaging said movable spring, and means for fixing the unoperated position of said card comprising a xed circular card of in sulating material having an aperture therein to hold the other one of said springs stationary relative to said movable circular' card and a second edge on said projection opposing said first edge and normally engaging said other one of said springs to position said movable card and to thereby serve as a backstop for said armature while said coil is deenergized.

HERMAN A. MILOCHE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,647,792 Gent Nov. 1, 1927 2,248,584 Reynolds July 8, 1941 2,422,861 ,S'krobisch June 24, 194'? 2,445,401 Langer July 20, 1948 

